Malicious network traffic, including widespread worm activity, is a growing threat to Internet-connected networks and hosts. In this paper, we propose a network intrusion detection system (NIDS) with semantics-aware capability. Our NIDS segregates suspicious traffic from the regular traffic flow, extracts binary code from the suspicious traffic, and performs semantic analysis on it to identify potential threats. Our contributions in this work are threefold: (a) we believe our prototype is the first NIDS that provides semanticsaware capability, (b) our implementation is more efficient than what is reported in [5], (c) our designed templates can capture polymorphic shellcodes with added sequences of stack and mathematic operations.
Walter J. Scheirer, Mooi Choo Chuah